What is freedom? It seems like such a simple question. Freedom is being able to do what you want to do. Allow me to explain it. I'm tired of working for a living. I'd rather collect taxes. So that's what I'm going to do: collect a kind of tax. You are ordered to estimate your income from the past 12 months, and write me a check for 1%. I have provided a mailing address for this purpose on my contact page ... What? You have a problem with my plan? Oh, I see. If you have to send me a check for the tax, then I have hurt your freedom to spend that money as you see fit. We have a conflict! And our basic problem is: we cannot enjoy freedom at the same time; we must settle for a limit. But what limit? Libertarians   believe freedom should be based on self-control. They describe freedom as being able to do what you want to do as long as it doesn't influence the equal right of others to do what they want to do. That is, freedom is being able to do what you like as long as you do not harm another person's life, liberty or property. You can build a set of legal and ethical   rules on the principle of self-control, and libertarians do. Their request for self-control often becomes more important than common sense, or even freedom itself. The definition rules out the freedom to steal, murder, and so on. Otherwise, you can do whatever you want. There is no problem until you realize that taxation is theft, that war is murder, and that national service is a form of slavery. Since only the government has a legal right to use force, libertarians focus on making the government smaller, or even going without it. The libertarians' definition of freedom is thus freedom from the government. Isn't it ridiculous? Which of the following statements is supported by libertarians according to the passage? A) National service should be canceled. B) People can do whatever they want. C) The government should have more power. D) They should be governed by the government.
A

Animals are considered to be endangered if the species is close to extinction throughout all or most of its environment. Animals become endangered for a variety of reasons. Some animals become endangered when their habitats contain resources for humans. For example, commercial forest cutting in the Amazon Rainforest has seriously reduced the population of many animal species and lead to the extinction of other groups. Land itself is an important resource to humans since it provides us with living space, and when people replace animal habitats with human habitats, it can lead to larger loss of natural species. Commercial and industrial operations may reduce land or water for animals and pollute their environment. Due to water pollution, the baiji, a fresh water dolphin native to China, was declared extinct, meaning it's unlikely the population can recover. Even noise pollution from human activities can lead to the disorder of animal behavior. Another cause that makes animals become endangered is over-fishing or over-hunting. Over-hunting whales led to near extinction of many species of whales. The introduction of a non-native species to a habitat may make animals become endangered. The native species may not defend against a new one, and the effects can be dangerous. In Australia, the introduction of the common house cat led to the extinction of the red-fronted parakeet and has seriously damaged the populations of several small animals. Introduced species can also bring new diseases with them. As a result, animals become endangered. Native animals may not have the power to fight against non-native diseases, and population levels can suffer. Another cause of disease is human-introduced chemicals. The use of DDT is believed to be one of the leading causes in driving the California Condor to near extinction. When animals become endangered, the entire food chain can be affected. For example, in 2008 disease seriously harmed the honeybee, which is largely responsible for pollinating   plants, including many fruits... Why is it dangerous to introduce a non-native species to a habitat? A) Native species are likely to die from the new diseases. B) It's hard for non-native species to survive. C) Non-native species will take up more space. D) Native species are so powerful for non-native species.
A

When Mr. David retired , he bought a small house in a village near the sea. He liked it and hoped to live a quiet life in it. But to his surprise, many visitors came to see his house in summer holidays, for _ was the most interesting building in the village. From morning to night, there were visitors outside the house. They kept looking into the rooms through the windows and many of them even went into the house. He decided to drive the visitors away. So he put a notice on the window. The notice said,"If you want to satisfy your curiosity ,come in and look around. Price: twenty dollars."Mr. David was sure that the visitors would stop coming, but he was wrong. More and more visitors came and Mr. David had to spend every day showing them around his house. "I came here to retire, not to work as a guide ", he said angrily. In the end, he sold the house and moved away. Mr. David put a notice on the window in order  _  . A) to drive the visitors away B) to satisfy the visitors curiosity C) to let visitors come in and look around D) to get some money out of the visitors

A